OBJECTIVE: Although antiretroviral treatment (ART) no longer requires 100% adherence, voluntary treatment interruption (VTI) still may have a negative impact on virologic success. Previous studies have shown that posttraumatic stress disorder (PTSD) is more prevalent in HIV-infected patients than in the general population. However, no study has yet investigated the relationship between PTSD and VTI. We analyzed this relationship using data from a French national survey representative of HIV-infected adults followed up in hospitals. METHODS: A total of 3,022 HIV-infected adults participated in the ANRS-VESPA2 survey (April 2011-January 2012) and answered a face-to-face questionnaire that included the Composite International Diagnostic Interview Short-Form to diagnose PTSD and assess sociobehavioral variables such as VTI. Multivariable logistic regression models were used to study the relationship between PTSD and VTI. RESULTS: Among the 2,768 ART-treated participants with available data for both PTSD screening and ART interruption (study sample), prevalence of PTSD was 13.3%, and 7.2% of individuals reported VTI during the previous month. After adjustment for being a female Sub-Saharan African immigrant and reporting harmful alcohol consumption (Alcohol Use Disorders Identification Test score ≥ 8), lifetime PTSD was found to be independently associated with VTI (adjusted odds ratio [95% CI] = 1.64 [1.07-2.53], P = .025). CONCLUSIONS: PTSD is highly prevalent in HIV-infected patients followed up in French hospitals and is a significant predictor of VTI. PTSD is a psychiatric disorder that is still underdiagnosed and undertreated in many countries despite its negative consequences on health behaviors. As there is evidence of effective treatment for PTSD, HIV care providers need to be trained in screening for this disorder.